Rand Paul: Boehner Will Be Overthrown If He Passes Senate Immigration Bill

"He has to hold the line. If he passes -- if he allows something to pass out of conference that looks anything like the Senate bill, and it is passed with a majority of Democrats, I think that will be the final thing he does as Speaker," Paul told Laura Ingraham's radio show on Friday. "I think he knows that, and I think he's going to be very cautious."

Paul said he'd support "a much more limited bill that emphasizes border security first" and called on supporters of reform to "dial it back."

"I'm worried about conference," he said. "And what I would say is, the only way to avoid a problem with conference is for the Speaker of the House to say we are not going to conference and we will not allow a vote on anything coming out of conference that resembles a vote on the Senate bill."